[hibernate-issues] [JIRA] (HHH-17026) Object serialization not working with @DiscriminatorColumn and Kotlin

Marco De Toma ( https://hibernate.atlassian.net/secure/ViewProfile.jspa?accountId=557058%... ) *created* an issue Hibernate ORM ( https://hibernate.atlassian.net/browse/HHH?atlOrigin=eyJpIjoiODc4OWYyMjNm... ) / Bug ( https://hibernate.atlassian.net/browse/HHH-17026?atlOrigin=eyJpIjoiODc4OW... ) HHH-17026 ( https://hibernate.atlassian.net/browse/HHH-17026?atlOrigin=eyJpIjoiODc4OW... ) Object serialization not working with @DiscriminatorColumn and Kotlin ( https://hibernate.atlassian.net/browse/HHH-17026?atlOrigin=eyJpIjoiODc4OW... ) Issue Type: Bug Affects Versions: 6.2.7 Assignee: Unassigned Created: 02/Aug/2023 03:56 AM Priority: Blocker Reporter: Marco De Toma ( https://hibernate.atlassian.net/secure/ViewProfile.jspa?accountId=557058%... ) First of all, I apologise in advance if this is the not right place to report this bug. I encounter this error after upgrading to hibernate 6 but, based on my findings, it occurs only with Kotlin (it works properly in Java). I decided to open a ticket here because it works properly with Hibernate version 5.x Context I have this table CREATE TABLE vehicles ( id uuid DEFAULT random_uuid(), vehicle_type varchar (255) not null , brand varchar (255) not null ); insert into vehicles (vehicle_type, brand) values ( 'CAR' , 'Audi' ) and defined two entities with SINGLE_TABLE hierarchy: @Entity @Table(name = "vehicles") @DiscriminatorColumn(name = "vehicle_type", discriminatorType = DiscriminatorType.STRING) @Inheritance(strategy = InheritanceType.SINGLE_TABLE) abstract class VehicleKotlin( @Id open var id: UUID, @Column(name = "brand") open var brand: String, ) @Entity @DiscriminatorValue("CAR") data class CarKotlin( @Id override var id: UUID, override var brand: String, ) : VehicleKotlin( id = id, brand = brand, ) Error When I try to query the database FROM VehicleKotlin WHERE brand =’s it seems like that the serialization does not work work properly. As you can see in the attachment, id and brand are null while VehicleKotlin.id` and`VehicleKotlin.brand` are set with the right values (but they don’t even exist in the model). In this demo ( https://github.com/detomarco/hibernate-bug-report ) you can find the same code work properly in Java but not in Koltin. Thank you in advance ( https://hibernate.atlassian.net/browse/HHH-17026#add-comment?atlOrigin=ey... ) Add Comment ( https://hibernate.atlassian.net/browse/HHH-17026#add-comment?atlOrigin=ey... ) Get Jira notifications on your phone! Download the Jira Cloud app for Android ( https://play.google.com/store/apps/details?id=com.atlassian.android.jira.... ) or iOS ( https://itunes.apple.com/app/apple-store/id1006972087?pt=696495&ct=Em... ) This message was sent by Atlassian Jira (v1001.0.0-SNAPSHOT#100233- sha1:8d17c5d )